Which of the following is true for Lasers?
Correct answer: C. Coherent monochromatic light is emitted
- A. Electrons are emitted
- B. Stimulated emission of electrons is needed
- C. Coherent monochromatic light is emitted
- D. There is a population inversion of photons
Explanation
A and B are incorrect because photons are emitted. D is incorrect because population inversion of atoms is achieved. C is correct because it is true that a laser emits coherent and monochromatic light.
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About Atomic Spectra
Atoms emit or absorb light at specific wavelengths because electrons occupy quantized energy levels and change levels by absorbing or releasing photons. The topic covers emission and absorption spectra, spectral series, hydrogen’s line spectrum, energy-level transitions, and the relation between wavelength, frequency and photon energy.
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